Utilize your sleeping bags: the original air mattresses. Create a pillow top over an inflated air bed with open sleeping bags, blankets or memory foam. The air inside of the mattress will gradually cool overnight, and likely make you colder than a regular bed. Pad it for comfort and warmth.
When did air mattresses come out?
The first air mattress was invented in 1889 by the Pneumatic Mattress & Cushion Company in Reading, Massachusetts.